A new plan for 3 GeV synchrotron radiation facility in JapanWataru Utsumi1) and Masaki Takata2)3)

1)Institute for Advanced Synchrotron Light Source, QST, Japan; utsumi.wataru@qst.go.jp

2)Photon Science Innovation Center, Japan3)Tohoku University, Japan

Japanese government has recently decided to build a new 3 GeV-class synchrotron radiation facility in the “Aobayama new campus” of Tohoku University, which is located in the Northern Eastarea, Japan. It is a high brilliance light source by an electron accelerator system combined with a linac and a 3 GeV storage ring, which covers the spectral regions from VUV to hard x-rays.

The key concept of our new synchrotron radiation facility is "advanced and stable light source to create innovations in science and technology". Its machine parameters are as follows.•Ring Energy: 3 GeV•Ring Current: 400 mA•Ring Circumference: 349 m•Emittance: 1.1 nmrad•Brilliance: 1021 photons/s/mrad2/mm2/0.1%b.w. (@1KeV)•Number of beamlines: 26 (10 beamlines will be constructed at an early stage)

The synchrotron radiation spectrum ranges from the VUV and soft X-ray (50-1000 eV, including the sharpest core levels for optimum chemical sensitivity) through the "tender X-ray" region (1-5keV, covering Mg, Al, Si for earth science and P, S for biochemistry) all the way to hard X-rays (> 5 keV for protein crystallography, environmental science, and chemistry in realistic environments).

The construction will be made by the collaboration of public-private regional partnerships. Total budget (10 beamlines included) is about 36 billion Japanese Yen. The site preparation work startedin March of 2019, and the first beam is scheduled in 2023.

Rendering image of a new 3 GeV synchrotron radiation facility inthe “Aobayama new campus” of Tohoku University, Japan

SPring-8/SACLA

3GeV Projectin Tohoku

TokyoFirst light expectedin FY2022

350 km from Tokyo

3GeV storage ring parameters

Four-bend achromat lattice

A 4-bend achromat lattice for low emittance with short circumference. The horizontal beam size at the undulator center is 1/3 of SPring-8.The vertical beam size is similar to SPring-8.

BL Number BL name Planned experiments Insertion device Energy range (polarization) Energy

resolution Beam size

BL-I X-ray operando spectroscopy∙ Ambient-pressure X-ray photoelectron

spectroscopy∙ Ambient-pressure X-ray absorption fine structure

spectroscopy∙ X-ray diffraction

In-vacuum plane

undulator2-20 keV (horizontal linear polarization) E/△E=

7,000 100 nm

BL-II X-ray structural and electronic-state total analysis

∙ Scanning transmission X-ray microscopy∙ Small-angle/wide-angle X-ray scattering∙ X-ray absorption fine structure spectroscopy

Multipole wiggler 2-20 keV (horizontal linear polarization) E/△E=

7,000 50 μm

BL-III X-ray multiscale structure analysis∙ X-ray absorption, imaging∙ Phase contrast imaging∙ Scanning X-ray fluorescence imaging∙ X-ray diffraction∙ X-ray fluorescence holography

Multipole wiggler 4.4-30 keV (horizontal linear polarization) E/△E=

7,000 50 μm

BL-IV X-ray coherent imaging∙ Coherent X-ray diffraction imaging∙ X-ray ptychography∙ Ptychography X-ray absorption fine structure

spectroscopy

In-vacuum plane

undulator

3.1-20 keV (circular polarization)2-20 keV（horizontal linear polarization）3.1-20 keV (vertical linear polarization)

E/△E=7,000

50μm（unfocused）

100 nm（focused）

BL-V Soft X-ray magnetic imaging

∙ Soft X-ray phase-contrast imaging∙ Scanning transmission imaging∙ Scanning X-ray fluorescence imaging∙ Soft X-ray magnetic imaging∙ X-ray magnetic circular dichroism∙ X-ray magnetic linear dichroism∙ X-ray magneto-optical Kerr effect

APPLE undulator

0.18-1.2 keV (circular polarization)0.13-2 keV (horizontal linear polarization)0.23-2 keV (vertical linear polarization)

E/△E=10,000-30,000 < 50 nm

BL-VI Soft X-ray electronic state analysis ∙ Nanoscale photoemission spectroscopy∙ Resonant Inelastic X-ray scattering

APPLE undulator

0.05-1.0 keV (horizontal linear polarization)0.05-1.0 keV (vertical linear polarization)

E/△E=10,000-30,000 < 50 nm

BL-VII Soft X-ray operando spectroscopy∙ Near ambient pressure X-ray photoemission

spectroscopy∙ Near ambient pressure X-ray absorption fine

structure spectroscopy

APPLE undulator

0.13-2 keV (horizontal linear polarization)0.23-2 keV (vertical linear polarization)

E/△E=10,000-30,000 < 50 nm

BL-VIII Soft X-ray nanoscale photoemission spectroscopy

∙ Nanoscale spin-resolved angle-resolved photoemission spectroscopy

APPLE undulator

0.05-1.0 keV (circular polarization)0.05-1.0 keV (horizontal linear polarization) 0.05-1.0 keV (vertical linear polarization)

E/△E=10,000-30,000

50 nm-10 μm

BL-IX Soft X-ray nanoscale absorption spectroscopy

∙ X-ray magnetic circular dichroism∙ X-ray magnetic linear dichroism∙ X-ray magneto-optical Kerr effect∙ X-ray linear dichroism∙ X-ray ferromagnetic resonance spectroscopy

SegmentedAPPLE

undulator

0.18-2 keV (circular polarization)0.13-2 keV (horizontal linear polarization)0.18-2keV (vertical linear polarization)

E/△E>10,000

50 nm-10 μm

BL-X Soft X-ray superhigh-resolution resonant inelastic scattering

∙ Superhigh-resolution resonant inelastic X-ray scattering

APPLE undulator

0.25-1.0 keV (circular polarization)0.25-1.0 keV (horizontal linear polarization)0.25-1.0 keV (vertical linear polarization)

E/△E>150,000 < 500 nm

• Storage ring with 350 m circumference • Injector linac of 110 m long

Accelerator system

Storage ring349 m

Beam transport

Linear accelerator (linac) 110 m

Experimental hall

3 GeV accelerator complex

The accelerator for the new 3GeV synchrotron radiationfacility is required to be (1) compact with less than 350 mcircumference, (2) in stable top-up operation combininghigh performance linear accelerator and new injectortechnology, (3) at high cost performance to realize stableand reliable light source along with brightness.

Beamlines

Schedule

Facility location

In the first phase, we are planning to construct the 10 beamlines listed below in view of (1)effective use of the low-emittance light source, (2) needs of academia and industries, and (3)complementary roles to existing synchrotron facilities in Japan.

Four out of the ten beamlines will allow access to highly brilliant tender X-rays from 2 to 5keV or higher for the purpose of X-ray coherent diffraction imaging and X-ray operandospectroscopy. The rest are soft-X-ray beamlines covering an energy range from 50 eV to 2keV, devoted to various spectroscopy experiments. The brilliance and photon flux in thisenergy range are expected to be 10-100 times as high as those available at SPring-8.

Science Park Zone

AobayamaStation

Graduate School of Pharmaceutical Sciences

Graduate School of Information Sciences

Graduate School of Engineering

New Industry Creation Hatchery Center (NICHe)

Welfare facilityAobayama Commons

University House

Graduate School of Agricultural Science

Plant Field Graduate School of Environmental Studies

International Research Institute of Disaster Science

Center for Innovation Electronic Systems (CIES)

Graduate School of Science

New 3 GeV synchrotron radiation facility is planned to be built at Aobayama newcampus of Tohoku University and 15 minuets walking distance from Aobayamastation which is 7 minuets form Sendai station.

Collaborating with Tohoku University not only academic use but also industrial useis expected. Science Park Zone is also planed to build next to the facility andaccelerate scientific research and innovation.

The project to build new synchrotron radiation facility has startedin 2019 and scheduled to start operation in 2023. At the beginning10 beam lines will be operating.

The project is driven by collaboration between QST and thepartner with sharing responsibility. The blue lines, which areaccelerator and part of beam lines, are responsible for QST and theorange lines, which are mail building, satellite building, landpreparation and part of beam lines, are for the partner.

2019 2020 2021 2022 2023

Accelerator（Linac and storage ring）

Beam lines

Main building

Satelitebuilding

Land preparation

Storage ring

Injector (Linac) （Installation/Alignment）

Controller, Security system

first beam

（Installation/Alignment）

※ coupling = 1 % is assumed

σx = 316 mmσy = 4.9 mm

x[mm]

SPring-8

σx = 121 mmσy = 5.8 mm

x[mm]

New 3GeV ring

1.0-1.0-1.0

1.0

1.0-1.0-1.0

1.0

Beam size at undulator

Lattice parameter

Beam energy E (GeV) 2.998

Lattice structure 4bend achromat

Circumference C (m) 348.8432

Number of cells Ns 16

Long straight section (m) 5.4400 × 16Short straight section (m) 1.6427× 16

Betatron tune x / y 28.17 / 9.23

Natural chromaticity x / y -60.50 / -40.99

Natural horizontal emittance (nmrad) 1.14

Momentum compaction factor α 0.000433

Natural energy spread σE/E (%) 0.0843

Lattice functions at LSS βx / βy / ηx (m) 13.0 / 3.0 / 0.0

Lattice functions at SSS βx / βy / ηx (m) 4.08 / 2.962 / 0.052

Damping partition number Jx / Js 1.389 / 1.611

Damping time τx / τy / τs (ms) 8.091 / 11.238 / 6.976

Energy loss in bends (MeV/turn) 0.621

RF frequency (MHz) 508.75905

Harmonic number h 592

Beam size at long straight σx/σy 121/5.8

•Ring Energy: 3 GeV•Ring Current: 400 mA•Ring Circumference: 349 m•Emittance: 1.1 nmrad•Brilliance: 1021 photons/s/mrad2/mm2/0.1%b.w. (@1KeV)•Number of beamlines: 26 (10 beamlines will be constructed at an early stage)

• A test half-cell consisting of 2 combined-B, 5 Q and 5 SX lined up on3 girders.

• Performance study of newly fabricated magnets• Establishment of precise alignment procedure of the magnets.

Test half-cell

Quadrupole magnet Sextupole magnetBending magnet